>I need pointers to good reverse engineering tools (documentation,>decompilation, etc.) to (mainly) document large legacy business>programs written in 370 assembly language. Any suggestions?

Well, thanks for all the suggestions I received. Must of them targeted
the disassembly of "machine" code programs. However, I'm not so much
looking for tools to disassembly "machine" code.

What I'm really after are tools that can help a programming team to
better document 370 assembly "source" code. Tools that can provide
sophisticated cross-references, with the help of a data dictionary
provide more readable listings, automatically draw flow-charts and
other pictorial views of programs, warn about data layout conflicts
and intersections, and help in the conversion process to a higher
level language like, say, COBOL.

Basically this implies a system that can from a given set of "source"
370 assembly files build a graph-like internal representation (IR)
with all computed, given and inferred dependencies (both reflecting
control flow and data intersections), and, perhaps with human help,
produce from this richer IR a better set of documentation and,
eventually, a partially complete higher level code equivalent (with
some marks indicating the need for further hand manipulation).

Furthermore, the programs I would like to better document (and some
convert) are reasonably clean business code (VSAM files, CICS,
records, and simple data manipulation) as opposite to normally more
convoluted systems programming type of code. I believe this greatly
simplifies the "re-engineering" process.

Any further suggestions on tools (commercial or otherwise) to help
with the above situations?